It is not the norm. Open source projects sponsored by a commercial organization tied to that project might be nominally controlled by a foundation, but that fou

It is not the norm. Open source projects sponsored by a commercial organization tied to that project might be nominally controlled by a foundation, but that foundation isn’t effectively controlled by a single person in their private capacity, who has secretly granted the commercial entity an exclusive, irrevocable commercial license. I don’t know if there is past precedent, but it’s certainly not the norm. What would be more normal is a company more or less owning the open source software and simply licensing it under a permissive license and then having a closed source or open core fork. An example there would be any number of Red Hat projects.